1. Field of the Invention
The present invention relates to a cooling system and method for cooling a heat producing system.
2. Background Art
Vehicles today are under an ever increasing demand to do more in less space. For example, an engine in a large commercial vehicle will typically provide torque to power the vehicle, and will also provide power to a variety of vehicle subsystems. Some of the subsystems may be directly driven by the engine through a mechanical link, while others may be operated by electrical power received from a generator, which itself is connected to the engine. As the number of these vehicle subsystems increases, so to does the demand on the engine. Therefore, there is a need to ensure an adequate cooling system for the engine so that it does not overheat or cause damage to vehicle components in close proximity to it. In addition, increasingly stringent emissions requirements can place additional demands on an engine cooling system, as the overall thermal output of the engine is closely managed to help meet the emissions requirements.
The increasing number of requirements placed on the engine can be the cause of increased size and complexity of the engine and its subsystems, including its thermal management system. Of course, many of these same concerns are present in other heat producing systems, for example a fuel cell or an engine used to drive an electrical generator, just to name two. In addition, other systems within a vehicle—i.e., systems other than the engine—may also require thermal management, further increasing the size and complexity of the thermal management system.
A conventional thermal management system may include one or more heat exchangers which are configured to facilitate heat dissipation from a temperature control fluid which receives heat from one or more heat producing systems. For example, in the case of a vehicle, a heat exchanger may be in the form of a radiator which has an engine coolant flowing therethrough. The coolant flows around the engine, absorbing heat from the engine, and then flows through the radiator where heat from the coolant is dissipated to the ambient air. Typically, one or more fans are used to move air through the radiator to increase the heat dissipation from the engine coolant to the ambient air. In the case of large vehicles, or other systems which produce a large amount of heat, it may be desirable to use a plurality of fans to move air through the radiator or other heat exchanger, rather than one large fan. Accordingly, it would be desirable to have a cooling system for a heat producing system, such as an engine in a vehicle, which uses a plurality of fans to efficiently move air through one or more heat exchangers to facilitate thermal management of the heat producing system.